1. Field of the Invention
The present invention relates to applying materials to substrates, and more particularly, to applying metered quantities of materials, such as topping materials, to food substrates, such as pizza bases.
2. Description of the Related Art
The current industrial technique for applying toppings to pizza bases employs a slow-moving conveyor to discharge the toppings onto pizza bases below. A mound of topping material is applied to the upper run of the slow-moving conveyor and is discharged as a "waterfall" using a rotating brush at the end of the slow-moving conveyor. Pizza bases are carried on a separate conveyor located underneath the slow-moving conveyor so as to pass through the "waterfall" of topping material. An example of this conventional technique is illustrated in FIG. 6. FIG. 7 shows a top view of the lower conveyor of FIG. 6, conveying pizza bases in three lanes.
In this conventional technique, however, there is little control of the amount of material applied to each base or its distribution, because a varying amount of the topping material continuously falls off the end of the top conveyor and is randomly distributed below, regardless of whether a pizza base is properly aligned underneath on the lower conveyor. Thus, there is also likely to be much waste of the topping, because much of the topping does not even land on the pizza base.